BETA 181 Specification
Cartridge Type Electret Condenser
Polar Pattern Cardioid / Supercardioid / Omnidirectional / Bidirectional
Frequency Response 20 to 20,000 Hz
Output Impedance 110 Ω
Maximum SPL Cardioid: 149.0 dB SPL
(1 kHz at 1% THD, 1kΩ load) Supercardoid: 152.0 dB SPL
Omnidirectional 154.0 dB SPL
Bidirectional 153.5 dB SPL
Signal-to-Noise Ratio Cardioid: 73.5 dB
(referenced at 94 dB SPL at 1 kHz; Supercardoid: 72.5 dB
S/N ratio is difference between 94 dB SPL and Omnidirectional 70.5 dB
equivalent SPL of self noise, A-weighted Bidirectional 71.0 dB
Dynamic Range Cardioid: 128.5 dB
(at 1 kHz, 1 kΩ load) Supercardoid: 129.5 dB
Omnidirectional 130.5 dB
Bidirectional 130.5 dB
Clipping Level 7.5 dBV (2.4 V)
(1 kHz at 0.25% THD, 1kΩ load)
Self-Noise Cardioid: 20.5 dB
(equivalent SPL, A-weighted, typical) Supercardoid: 22.5 dB
Omnidirectional 23.5 dB
Bidirectional 23.0 dB
Common Mode Rejection ≥55 dB
(20–20,000 Hz)
Polarity Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
Power Requirements 11–52 VDC phantom power (IEC-61938), 1.2 mA
Weight Net: 145 g (5.1 oz.)
